Instructions:

1. Adjust the seat of the sled machine so that your knees are at a 45-degree angle.
2. Sit on the sled machine with your back against the backrest and your feet shoulder-width apart on the footplate.
3. Grip the handles on the sides of the seat for stability.
4. Push the footplate away from your body by extending your legs, keeping your heels on the footplate.
5. Pause for a moment at the fully extended position.
6. Slowly bend your knees and lower the footplate back towards your body, controlling the movement.
7. Repeat for the desired number of repetitions.